TMJ & Cranio-Mandibular Dysfunction

Cranio-mandibular dysfunction is a term which describes a group of symptoms which result when the chewing muscles and the tempero-mandibular joints (jaw-joints) do not work together correctly. TMJ-problem is often used as a synonym for the same group of symptoms. The tempero-mandibular joints connect the lower jaw to the skull. The position of your teeth can also affect the position of your joints. In fact, the most common cause of cranio-mandibular dysfunction relates to your teeth. If the bite is not correct it can have an effect both on the chewing muscles and on the joints. When the teeth do not come together at the same time, the chewing muscles have to work much harder, and this can result in muscle tenderness and pain.

The jaw-joint consists of a ball and a socket. The ball is a part of the lower jaw and the socket is a part of the skull bone. Between these two parts there is a disc made of cartilage. The disc acts as a cushion and allows the joint to work smoothly. The disc in the tempero-mandibular -joint is held in place by muscles. If the bite is not correct, the joint can be pulled out of alignment; on one or both sides. As a consequence, the cartilage disc is most frequently pulled forward, and the disc is said to be displaced. A mild displacement of the disc forward often causes a clicking sound in the joint, when opening fairly wide.

Though infrequent, surgery is sometimes required to correct a damaged joint. Ultimately, the dentist will stabilize the bite so that the teeth, muscles and joints all work together without strain.

Possible symptoms from cranio-mandibular dysfunction:

Clenching or grinding of the teeth

Headaches especially when waking up in the morning; most often centered in the forehead or temple regions

Pain behind the eyes

Ear ache

Neck pain

Clicking of the jaw-joints

Pain in or around the jaw-joints

Sensitivity in teeth and sore teeth when chewing

Abrasion of teeth (chipped, uneven or reshaped teeth due to grinding)

Reduced opening capacity

Locking of the jaws

Treatment includes adjustment of the occlusion (the contacts between the upper and lower teeth). Most often a night guard has to be used, to prevent direct contact between the upper and lower teeth. A very important effect of the night guard is that it relaxes the chewing muscles.